BEIJING — The average PM2.5 density in Beijing stood at 34 micrograms per cubic meter of air from January to August this year, the lowest for the period on record, authorities said on Sept 26.

The average PM2.5 density in the city was 18 micrograms per cubic meter in August, also a record low, according to the municipal ecology and environment bureau.

The Chinese capital reported 29 days of good air quality in August, or 93.5 percent of the month, the bureau said.

Beijing authorities have taken a slew of measures to tackle air pollution, including promoting new-energy cars and monitoring diesel vehicles.

PM2.5 — airborne particles smaller than 2.5 micrometers in diameter — pose serious health risks.